Method of testing cigarette paper

ABSTRACT

In a cigarette making system the porosity of the paper web forming the wrapper of the cigarettes is tested, for example by means of a pneumatic test device, and a signal thus obtained is fed to a cigarette inspector device which tests the cigarettes for leaks in the wrapper; the inspector device thus is compensated for variations in the paper porosity.

I Umted States Patent [191 [1 1 3,720,095

Molins H lMarch 13, 1973 METHOD OF TESTING CIGARETTE [56] References Cited PAPER UNITED STATES PATENTS [75] inventor: Desmond Walter Molins, Deptford,

Ludo", Wand i'ii'il 121322 52122;; "532723 [73] Assignee: Mollns Organization Limited, London, England Primary Examiner-S. Clement Swisher [22] Filed: och 7 1968 Attorney-Craig, Antonelii & HI"

[2!] Appl. No.2 765,375 [57] ABSTRACT In a cigarette making system the porosity of the paper 30 Forei n A lication Prlorit Data web forming the wrapper of the cigarettes is tested, 1 s W y f l b i t' t td d or examp e y means 0 a pneuma 1c es evice, an Oct. 11, Great Bl'ltaln a signa t us ob a ed s e to a c g e pector device which tests the cigarettes for leaks in the [52] "73/38 wrapper; the inspector device thus is compensated for [51] "Golm 3/02 variations in the paper porosity. [58] Field of Search ..73/37.7, 38, 40

1 Claim, 3 Drawing Figures PATENTEDMRRI ama METHOD OF TESTING CIGARETTE PAPER This invention relates to improvements in the manufacture of cigarettes, cigars and the like all being rodshaped tobacco articles having an air-permeable filler enclosed within an open-ended wrapping. All such articles are hereinafter to be understood to be included in the term cigarettes. More specifically the invention is concerned with cigarette manufacture in which a test is made to reveal and reject any cigarettes having leaky wrapping which would make them difficult or impossible to smoke.

in recent times proposals have been made to include in cigarette manufacture the step of testing cigarettes in a continuous stream by establishing an air pressure difference between the inside and the outside of individual cigarettes, detecting the resultant air flow which occurs through the wrapping and using this to effect rejection of faulty cigarettes. In general, rather complicated and costly apparatus has been required to carry out this test on a fast-moving stream of cigarettes.

It is an object of the present invention to provide an improved method of and apparatus for manufacturing cigarettes which includes a step of testing to reveal cigarettes having leaky wrappings.

According to one aspect of the present invention there is provided'a method of manufacturing cigarettes wherein a continuous wrapped tobacco rod is formed from a stream of tobacco and from a continuous web of wrapping material which method includes the step of continuously examining the web of wrapping material before it is formed into the rod for its air porosity and using the results of such examination in rejecting unsatisfactory cigarettes. Cigarettes can be rejected according to the results of this examination. The method can be used for testing mouthpiece cigarettes and include testing the joints of such cigarettes for air leaks.

The method can include testing the cigarettes for air leaksin their wrappings and, refjecting unsatisfactory cigarettes according to the results of such testing and using the results of said examination in controlling such testing.

The examination may be effected by establishing an air-pressure difference across the wrapper web and detecting any air flow which occurs. This could be done by running the web over a suction shoe, the air flow being detected either by the effect it has on the pressure in the suction shoe or by its effect on the air pressure in a detection chamber formed on the other side of the wrapper to sense such air flow.

Alternatively the wrapper web could be examined electrostatically by establishing an electrical potential difference across the wrapper web and detecting any discharge occurring through the web.

The invention also extends to include examining the manufactured tobacco rod for faults which may have been introduced during the rod-forming process and one way of doing this is disclosed in my U.S. Pat. application Ser. No. 765,374, filed Oct. 7, I968, relating to cigarette testing. It can also include testing the joint of mouthpiece cigarettes in the way disclosed in my U.S. application Ser. No. 765,376 filed Oct. 7, 1968.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawing in which:

FIG. 1 is a vertical sectional view of a wrapper testing device,

FIG. 2 is a plan view of FIG. 1, and

FIG. 3 is a section on the line lIl-lll of FIG. 1.

The testing device shown in the drawing is used to test a continuous moving web 1 of cigarette paper for any holes or excessive porosity it may have which would render undesirable a cigarette made from the portion of the web including such a fault as the smoker in drawing on the cigarette would tend to draw air through the fault.

The device comprises a lower suction chamber 2 communicating with a suction source through a port 3 and an upper test chamber 4 having a bleed hole 5 communicating with atmosphere, to provide a source for air drawn through the wrapper web 1 into the suction chamber 2, and having a port 6 communicating with an air-pressure-sensitive testing device. Grooves 7 accommodate the edges of the web 1 as it runs through the device.

In operation the paper web I is fed continuously through the device while suction is applied continuously to the chamber 2 and some air flow occurs through the web 1 thereby reducing the pressure in the chamber 4. This pressure is continuously monitored by the pressure sensitive testing device. Any holes or excessive porosity'in the web 1 will result in an increased air flow through the paper and a greater pressure drop in the chamber 4. This is noted by the pressure-sensitive testing device and can be used to reject the cigarette or cigarettes incorporating that portion of paper, from the production stream.

The device would be mounted on a cigarette-making machine to examine the paper as it runs from its bobbin to the garniture where the tobacco rod is made. For example the device would be applied to a cigarette making machine as described in U.S. Pat. No. 3,030,965. FIG. 8 of that patent, for example, shows a paper web 106 being fed into a garniture in which the web is wrapped round a tobacco stream to form a continuous cigarette rod. This continuous rod is then cut into cigarette lengths, for example by means of a cut-off mechanism as described in U.S. Pat. application Ser. No. 783,983, filed Dec. 16, 1968. Then the wrapper of each cigarette may be tested by means of a pneumatic cigarette inspector device as described for example in U.S. Pat. No. 3,266,295. The pressure signal from the device according to the present application may be fed to the cigarette inspector device to provide compensation at the inspector for varying paper porosities.

The invention is also of advantage when the cigarette-manufacturing process includes the step, or apparatus for performing the step, of testing each of the cigarettes individually in a manner such as that disclosed in U.S. application Ser. No. 643,571, filed June 5, l967 in the name of Eryk Stefan Doerman now U.S. Pat. No. 3,485,084. In this way the results of examining the wrapper web can be used to improve the individual cigarette testing by, for example, adjusting the sensitivity of the test according to the porosity which the wrapper web exhibits during its examination.

What I claim as my invention and desire to secure by Letters Patent is:

l. A paper porosity testing device comprising a body having an internal chamber, a pair of opposed slots in the body for leading a paper strip into and out of the chamber, a pair of grooves in the chamber wall for guiding the paper strip between the two slots while it is in the chamber and a pair of ports in the body for applying pressure to one side of the paper strip and for measuring the pressure on the other side of the strip.

* i i 1' K Patent NO. 3,720,095 r at d March 13, 1973 Inventor(s) Desmond Walter Molins It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Assignee incorrect. Should read:

-Mo1ins Machine Company Limited--.

Signed and sealed this 29th day of January 197E.

(SEAL) Attest: I

EDWARD M.FLETCHER,JR. RENE D. TEGTMEYER Attesting Officer Acting Commissioner of Patents FORM USCOMM-DC suave-Peg U,S GOVERNMENT PRINTING OFFICE: I959 '-366334 

1. A paper porosity testing device comprising a body having an internal chamber, a pair of opposed slots in the body for leading a paper strip into and out of the chamber, a pair of grooves in the chamber wall for guiding the paper strip between the two slots while it is in the chamber and a pair of ports in the body for applying pressure to one side of the paper strip and for measuring the pressure on the other side of the strip. 